Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page: https://medlineplus.gov/druginfo/meds/a682204.html

Sulfasalazine

pronounced as (sul fa sal' a zeen)

Why is this medication prescribed?

Sulfasalazine is used to treat ulcerative colitis (a condition which causes swelling and sores in the lining of the colon [large intestine] and rectum) and also to maintain improvement of ulcerative colitis symptoms. Sulfasalazine delayed-release (Azulfidine EN-tabs) is also used to treat rheumatoid arthritis in adults whose disease has not responded well to other medications or could not be tolerated. Sulfasalazine delayed-release (Azulfidine EN-tabs) is also used to treat polyarticular juvenile idiopathic arthritis (PJIA; a type of childhood arthritis that affects five or more joints during the first six months of the condition, causing pain, swelling, and loss of function) in children who have not been helped by other medications. Sulfasalazine is in a class of medications called anti-inflammatory drugs. It works by reducing inflammation (swelling) inside the body.

How should this medicine be used?

Sulfasalazine comes as regular and delayed-release (releases the medication in the intestine to prevent irritation to the stomach and to allow the medication to work in the intestine where its effects are needed) tablets. It usually is taken 3 to 6 times a day in evenly spaced doses throughout the day so that no more than 8 hours separates any two doses, if possible. For treatment of rheumatoid arthritis or polyarticular juvenile idiopathic arthritis, sulfasalazine delayed-release tablets are usually taken twice a day in evenly spaced doses throughout the day. Take sulfasalazine after a meal or with a light snack, then drink a full glass of water. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take sulfasalazine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow delayed-release tablets whole; do not crush or chew them.

Drink plenty of fluids while taking sulfasalazine.

Continue to take sulfasalazine even if you feel well. Do not stop taking sulfasalazine without talking to your doctor.

Other uses for this medicine

Sulfasalazine is also used to treat bowel inflammation, diarrhea (stool frequency), rectal bleeding, and abdominal pain in Crohn's disease. Talk to your doctor about the possible risks of using this drug for your condition.

What special precautions should I follow?

Before taking sulfasalazine,

  • tell your doctor if you are allergic to sulfasalazine; sulfapyridine; salicylate pain relievers such as aspirin, choline magnesium trisalicylate, diflunisal, magnesium salicylate (Doan's, others); balsalazide (Colazal); mesalamine (Apriso, Delzicol, Lialda, Pentasa); olsalazine (Dipentum); sulfa drugs; any other medications; or the ingredients in sulfasalzine tablets or delayed-release tablets. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had an intestinal obstruction (a blockage in your intestine), a urinary obstruction (a blockage of urine flowing out of the bladder), or porphyria (condition in which abnormal substances build up in the blood and cause problems with the skin or nervous system). Your doctor will probably tell you not to take sulfasalazine.
  • tell your doctor if you have an infection or if you have or have ever had an infection that keeps coming back. Also tell your doctor if you have or have ever had asthma, glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (an inherited blood disease), kidney stones, blood problems, or kidney or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking sulfasalazine, call your doctor.
  • you should know that this medication may decrease fertility in men. Fertility usually returns when the medicine is stopped. Talk to your doctor about the risks of taking sulfasalazine.
  • plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, and sunscreen. Sulfasalazine may make your skin sensitive to sunlight.
  • you should know that sulfasalazine should not be taken by people who have received the varicella virus (chicken pox) vaccine in the past six weeks because of the risk of Reye's syndrome (a serious condition in which fat builds up on the brain, liver, and other body organs).

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Sulfasalazine may cause side effects.

Tell your doctor if any of these symptoms are severe or do not go away:

  • yellow or orange discoloration of urine or skin
  • diarrhea
  • headache
  • loss of appetite
  • upset stomach
  • vomiting
  • stomach pain

If you have any of the following symptoms, stop taking sulfasalazine and call your doctor immediately:

  • rash, hives, itching or peeling or blistering skin
  • swelling of the eyes, face, lips, tongue, mouth, or throat
  • difficulty breathing or swallowing
  • swollen glands
  • fever, sore throat, chills, cough, night sweats, and other signs of infection
  • pale skin, tiredness, or shortness of breath
  • joint or muscle aches
  • yellowing of the skin or eyes
  • pain in the right upper part of the stomach
  • difficult or painful urination or cloudy, discolored or blood urine
  • chest pain
  • new or worsening cough
  • tiredness
  • unusual bleeding or bruising
  • weakness
  • seizures

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • nausea
  • vomiting
  • stomach pain
  • tiredness
  • seizures

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests before and during your treatment to check your response to sulfasalazine.

Do not let anyone else take your medicine. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Azulfidine®
  • Azulfidine® EN-tabs®
Last Revised - 02/15/2024